A researcher believes that college students today have different IQ scores than in previous years. To...

A researcher believes that college students today have different IQ scores than in previous years. To investigate this belief, he randomly samples 41 currently enrolled students and records their IQ scores. The scores have a mean of 111 and a standard deviation of 12.4. A local census taken 10 years ago shows that the mean IQ of students enrolled during that time was 115.

The degrees of freedom for this sample is                            [ Select ]                       ["41", "40", "39", "38", "-2.201", "-2.407", "2.704", "2.021", "-2.07", "+2.07", "-0.32", "+0.32", "reject the null hypothesis", "fail to reject the null hypothesis", "IQ is probably different", "IQ is not different"]

Using a two tailed alpha level of .01, the appropriate critical value is                             [ Select ]                       ["41", "40", "39", "38", "-2.201", "-2.407", "2.704", "2.021", "-2.07", "+2.07", "-0.32", "+0.32", "reject the null hypothesis", "fail to reject the null hypothesis", "IQ is probably different", "IQ is not different"]

The obtained value of the appropriate statistic is                            [ Select ]                       ["41", "40", "39", "38", "-2.201", "-2.407", "2.704", "2.021", "-2.07", "+2.07", "-0.32", "+0.32", "reject the null hypothesis", "fail to reject the null hypothesis", "IQ is probably different", "IQ is not different"]

What is your decision?                             [ Select ]                       ["41", "40", "39", "38", "-2.201", "-2.407", "2.704", "2.021", "-2.07", "+2.07", "-0.32", "+0.32", "reject the null hypothesis", "fail to reject the null hypothesis", "IQ is probably different", "IQ is not different"]

Is the IQ of currently enrolled college students different than in previous years?                            [ Select ]                       ["41", "40", "39", "38", "-2.201", "-2.407", "2.704", "2.021", "-2.07", "+2.07", "-0.32", "+0.32", "reject the null hypothesis", "fail to reject the null hypothesis", "IQ is probably different", "IQ is not different"]

Expert Solution

orchestra answered 1 year ago

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